Question: What does “complete unity” mean in John 17:23?

Question: What does “complete unity” mean in John:17:23I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me.
See All...? Does complete unity mean unity on the essentials such as the Trinity, Salvation by Grace Alone, and the Resurrection of Jesus? Or does it speak of unity on “non-essentials” also?

Response: 

Thank you for your question regarding what “complete unity” in John chapter 17 means. John:17:23I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me.
See All... reads, “I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me.”

The comparison is that since Jesus is “in them” and the Father is in Him, thus the outcome is that “they may [all] be made perfect in one.” This clearly involves more than an agreement on “essentials.” Rather, it speaks of a progressive unity that may only be reached when we leave this world (through death or the Rapture), which is the same agreement that the Son has with the Father. First John:3:2The same came to Jesus by night, and said unto him, Rabbi, we know that thou art a teacher come from God: for no man can do these miracles that thou doest, except God be with him.
See All... tells us, “Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is.”

Of that event, 1 Corinthians:15:52In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
See All... says, “In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.”

We shall be changed, and in that changing we shall move beyond the limitations of our life here, which is greatly influenced by the “flesh.” Although the prayer of Jesus will be answered fully in that we shall have perfect agreement and unity with every member of the Body of Christ, in the meantime our focus remains upon our... “endeavouring to keep the unity of the Spirit in the bond of peace” (Ephesians:4:3Endeavouring to keep the unity of the Spirit in the bond of peace.
See All...).